No Limb, No Problem!
Imagine
what it would be like to lose an arm, or a leg, and your body could simply grow
another. Believe it or not, modern science and technology are showing signs of
this one day being a possibility in humans. The process of limb regeneration,
by which a lost limb can be regrown, is already found in organisms such as
salamanders and starfish. Humans regenerate well with much simpler body parts,
like the epidermis, or the gut lining; but scientists have not yet had a major
breakthrough with this phenomenon. Slowly, but surely, evidence is being pieced
together to solve this mystery.
One
study conducted in 2013 on the axolotl, an aquatic salamander, showed signs of
macrophages playing a major role in this restoration. Macrophages are known to
play a major role in immune response, where they “eat” microscopic foreign
bodies that are harmful to the body. Amazingly, macrophages somehow know how to
distinguish between cells that are bad and need to be destroyed, and cells that
are good and can be left alone.
The
experimentation was done by depleting the macrophage count in some of the
salamanders and leaving others alone, and furthermore performing amputations on
both groups. The salamanders without macrophages were not able to regenerate
the lost limbs, while those with their macrophage counts still intact were able
to regrow them; showing a correlation between presence of macrophage and the
ability to regenerate. In the years following these experiments, it has
been revealed that yes, macrophages are important to this process, but there
are likely more elements to it that have yet to be revealed.
If scientists can figure out exactly how the
salamanders are able to do this, and find what genes are turned on in their
genetic code (and turned off in humans) to give them this special ability, it
might be possible to engineer a similar technique for human treatments.
Cracking the code on regeneration in these salamanders could one day help
humans have the same capability.
Published by Hannah Kullberg (2).
I wonder what the limitations would be to regenerate an arm of a human. Regenerating the arm of a salamander must be easier, at least in terms of how many cells must be replaced. I can imagine its possibility in an organism as complex as humans becasue salamanders also have central nervous systems, bones, and muscles. I wonder what the regeneration in humans would look like and how painful it would be.
ReplyDelete-Brooke Sullivan
Losing a leg or losing an arm means losing a very complex body part - one with muscle, bone, blood vessels, skin, nerves and much more. In salamanders their cells somehow "know" that when a body part is amputated, they most re grow the structure, and execute it in a way that it regenerates exactly what it needs to and nothing more. We know that things like human skin and the human liver can regrow, but if the entire liver is removed it cannot regrow itself - whereas in a salamander a limb can be amputated and regrown over and over. So, this is something that scientists are still figuring out. I am also intrigued to know what limb regeneration will look like in humans - hopefully we will find out someday soon!
Delete-- Hannah Kullberg (2)
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ReplyDeleteI find it very interesting that macrophages are so important to the regeneration process. Given that there are other species that also demonstrate the ability to grow limbs, are there any shared similarities in this regenerative mechanism? The fact that limb growth appears in a few unrelated species is pretty crazy, and I am curious about why it isn't a more popular survival strategy.
ReplyDeleteHarris Jackson (1)
I did some more research on this. As I said, there are other factors that play a role in this process. In salamanders, almost immediately after losing a limb cells rush to the site and a blastema forms. This blastema forms an outline for the limb and foot and allows it to regrow into the correct structure. This does not happen in humans. Instead the wound forms blood clots and it scabs and scars. Blastema formation also occurs in zebrafish and starfish, both with regenerative capabilities. So, this probably contributes to the reason why regeneration does not occur naturally in human limbs.
Delete--Hannah Kullberg (2)
I cannot imagine losing an arm, leg, or any body part for that matter. Being about to discover that salamanders with higher macrophage counts were about to regrow limbs is a start to apply this knowledge on humans. There are so many people with disabilities out there in the world and it would be life-changing for them if they were able to regrow a limb they lost. Even if this doesn't work out, technology and science continues to grow everyday to help make people's lives more accessible.
ReplyDelete-Posted by Catherine Tsang (3)
Hopefully they crack the code soon! Figuring out how to get this process working in humans would be an amazing break through, improving the lives of so many.
Delete--Hannah Kullberg (2)
Macrophages seem to play a major role in the regeneration process which really interests me. I cannot imagine that one day we will be able to regrow limbs of the human body. Looking at all the advantages in science we currently have I do not see why it won't be done in the years to come. If these salamanders can do it will be definitely be studied more and more to be able to find the exact mechanisms we can use from human bodies for regeneration of limbs.
ReplyDeletePosted by Sarah Aboody (1)
I agree, and I think that we are right around the corner from a break through.
Delete-- Hannah Kullberg (2)
I found it interesting how this research could help contribute to the possibility of humans being able to regenerate limbs. Also I wonder how studies on our livers have contributed to this same idea of regeneration, being that it is the only organ capable of regeneration.
ReplyDelete-Sunaina Sharma (3)
Liver regeneration is a very complex process and we still don't know everything about it. But it would make sense that there are similarities between liver regeneration, and limb regeneration.
Delete--Hannah Kullberg (2)
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ReplyDelete